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d) Please refer to the instrument set-up shown in Fig. 1 and the absorbance spectrum of Alexa Fluor 555 dye (abbreviated as A555) shown in Fig. 2. One day, our friend Bob was bored and decided to remeasure the absorbance of A555. He actually made the measurement twice; first with Yttrium PMTs, then second with Cesium PMTs (both the sample and reference PMTs were made of the same material during each measurement). Please draw two graphs, each showing the transmittance of light between 400 and 1000nm to both the sample and reference PMT, for the two PMT materials (i.e., two graphs with two plots each). The work function for Yttrium is 3.1eV and Cesium is 1.95eV